JPH08285720A - Leak test method for underground service piping system - Google Patents

Abstract

PURPOSE: To test leakage for every group of a plurality of consumers immediately as required. CONSTITUTION: In an underground service piping system comprising a supply side main piping 1 and a plurality of branch pipings 3 for a group of homes 2, a main plug 5 previously equipped with a test plug 6 is coupled between the main piping 1 and each branch piping 4. Upon elapse of a predetermined time after closing the main plug 5 and the main plug 4 on each home 2 side, variation in the pressure measured by a pressure gauge 8 coupled with the test plug 6 is compared.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leak inspection method for underground buried equipment piping.

[0002]

2. Description of the Related Art Household facility piping such as water supply or city gas is branched from each main piping on the supply side to each household through a main tap.

As the piping system, there are a common ditch system and an underground burying system. In the case of the common ditch method, it is easy to identify the leak location, but due to the high construction cost, the penetration rate is low,
Currently, underground buried type is generally the mainstream.

In the case of underground underground equipment piping, when a water pipe is damaged due to an earthquake or the like, or leakage from a gas pipe is predicted, water noise or odor is detected and the leakage point is specified. The work procedure of excavating the area around this and repairing the detection point is repeated. However, in reality, it is difficult to detect the leakage point with this method, and a considerable number of points must be dug up to identify it.

By the way, as one of the inspection methods, a test plug and a pressure gauge connected to the test plug are attached near the main plug of the supply side pipe, the main plug on the supply side and the valve on each consumer side are closed, and then the pressure is supplied to the piping path. In addition to the above, it is known to compare the pressure before and after a lapse of a certain time and inspect the presence or absence of a leakage portion in that section. This method cannot immediately detect and limit the leakage at a specific location, but has an advantage that the leakage location can be limited to a specific area.

[0006]

However, in this inspection method, the test plug must be attached each time the inspection is performed.
For this purpose, the piping pipe to be inspected must be cut and threaded, and then both sides of the test plug must be screwed and connected, which makes quick response difficult. The present invention is to solve the above problems, and an object thereof is to provide a leak inspection method for underground buried equipment piping that allows immediate inspection of a plurality of consumers for leaks as needed. is there.

[0007]

According to the method of the present invention, in the underground buried equipment pipe branched from the main pipe on the supply side to a plurality of consumer groups, a test plug is previously provided between the main pipe and each branch pipe. A pressure gauge before and after a lapse of a certain period of time is compared by a pressure measuring instrument connected to the test stopper after the main stopper and the valve on the side of each consumer are closed (claim 1). .

In the method of the present invention, it is preferable that the consumer group is sequentially hierarchically divided into a plurality of groups from the main pipe, and a main stopper provided with a test stopper is provided at a branch position from the upper group to the lower group ( Claim 2).

It is desirable that the pressure measuring device used in the present invention has a built-in pressurizing device, pressurizes the inspection point by the pressurizing device, and compares the initial pressure with the pressure change after a lapse of a certain period of time. 3) Furthermore, it is desirable that the pressurized fluid of the pressurizing device is a gas (claim 4).

[0010]

According to the constitution of claim 1, when a gas leak or a water leak is reported in a specific area, the test tap is immediately used after closing all the main taps in that area and all the valves of consumers in that area. You can check whether there is a leak.

According to the second aspect of the present invention, it is possible to sequentially inspect equipment pipes over a wide area from the original side to the end, and it is possible to determine that other areas are safe even if a leak occurs in a specific area.

In the case of claim 3, it is possible to confirm the presence or absence of leakage even if the supply is stopped in the event of an earthquake.

In the case of the fourth aspect, the invention can be applied to both water pipes and gas pipes.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows equipment piping for carrying out the inspection method according to the present invention. There are two types of facility piping, water and city gas, and the connection method differs depending on whether the fluid to be handled is water or fuel gas, but since they are similar, they are used as facility piping. Handle as a batch.

In the figure, the main pipe 1 on the supply side is connected to each consumer group, that is, each home 2 by an independent branch pipe 3. Each home 2 is provided with a home mains plug 4 and a meter, etc., through which home piping is made toward the terminal equipment installation place in each home 2.

A main plug 5 is interposed between the main pipe 1 and the branch pipe 3. The main plug 5 is housed in a manhole M excavated in the ground, and is normally closed by a manhole cover or the like. In addition, if each household 2 corresponding to the manhole cover is displayed, the inspection location can be easily specified.

A test plug 6 is integrated on the downstream side of the main plug 5, that is, on the connection side with the branch pipe. On the upper part of the test stopper 6, a connecting portion 6 which is opened and closed by a valve handle 7
a is protruding. The connecting portion 6a is normally closed with a cap nut or the like, but at the time of inspection, the cap nut is removed and the connecting union 8a of the pressure measuring instrument 8 is attached.

The pressure measuring device 8 incorporates an air compression device such as a compressor, a pressure gauge, a timer, a pass / fail judgment means, etc., and is provided immediately after a predetermined pressure is applied to the inside of the pipe through the test plug 6 by the pressurizer. The indicated pressure of the pressure gauge is compared with the indicated pressure after a lapse of a predetermined time, and the degree of pressure drop is determined to determine whether the pressure is normal.

Therefore, when inspecting for leakage,
If all of the main taps 5 and the main taps 4 of each household 2 are closed, a pressure measuring device 8 is immediately connected to the test plug 6 and an inspection is performed after pressurization, so that the presence or absence of leakage of each branch pipe 3 can be confirmed. Further, by pressurizing, for example, even when the supply side stops the supply at the time of the earthquake, the inspection can be performed quickly.
If it is judged that there is no leakage, branch pipe 3 in that area
Can be regarded as safe, and after that, only the end pipe in each home 2 needs to be inspected.

If it is determined that there is a leak, it is determined that there is a leak in the branch pipe 3 that connects each home 2 and the main tap 5.
After that, the branch pipe 3 can be individually inspected to detect and limit the leaked portion.

The pressure measuring instrument 8 can be used even if the pipe to be inspected is a water pipe. When incompressible water such as a water pipe is filled, the pressure gauge becomes sensitive to minute leaks, but in this case, by adding pressurized air to the pipe,
It is possible to eliminate the difficulty of leak determination due to a sharp drop in pressure at the time of a minute leak, and to obtain the same measurement accuracy as gas equipment piping.

FIG. 2 shows equipment pipes suitable for the above inspection method, which are sequentially hierarchically divided from the main pipe 1 into a plurality of branch pipes 3a, 3b ... Up to this point, a main stopper 5 having test stoppers is provided at a branch position from the upper group to the lower group. Therefore, in the case of the branch pipes 3a, 3b ... Which reach such ends, it is possible to sequentially inspect from the original side of the equipment pipes over a wide area to the end, and even if leakage occurs in a specific area, other areas are safe. It can be determined that there is, and by closing the main tap 5 only in the leaking area, the supply to other area groups can be continued as it is. On the other hand, in the leakage area, it is possible to recover the areas other than the cause area while sequentially detecting and limiting the leakage area from the upper group to the end.

[0023]

According to the leak inspection method for underground burial facility piping according to the invention of claim 1, when a gas leak or a water leak is reported in a specific area, the main plug in that area and the consumers in that area are reported. Immediately after closing all of the valves, the presence or absence of leakage can be confirmed through the test stopper, so that quick response can be taken.

According to the second aspect of the present invention, it is possible to sequentially inspect from the original side to the end of the equipment piping over a wide area, and even if there is a leak in a specific area, it can be judged that other areas are safe, It is possible to promptly limit the detection of the leaked part until the above and to recover sequentially.

In the case of claim 3, since it is possible to confirm the presence or absence of leakage even if the supply is stopped in the event of an earthquake, it is possible to quickly confirm the safety before restoration.

In the case of claim 4, the present invention can be applied to both water pipes and gas pipes, and particularly when applied to water pipes, a leak judgment due to a sudden drop in pressure at the time of a minute leak can be made. It eliminates the difficulty of and can measure with the same measurement accuracy as gas equipment piping.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a connection state of equipment piping for carrying out the method of the present invention.

FIG. 2 is an explanatory diagram showing equipment piping suitable for the above inspection method.

[Explanation of symbols]

 1 Supply side main piping 2 Consumer (household) 3 (3a, 3b) Branch piping 4 Home side main plug 5 Main plug 6 Test plug 8 Pressure measuring instrument

Claims (4)

[Claims] 1. An underground burial facility pipe branched from a main pipe on the supply side to a plurality of consumer groups, a main plug having a test plug arranged in advance is provided between the main pipe and each branch pipe, and the main plug is provided. And a method for inspecting leaks in underground buried equipment piping, which comprises closing the valves on the side of each customer and comparing the pressure change before and after a certain period of time with a pressure measuring instrument connected to the test plug. 2. The consumer group is sequentially hierarchically divided into a plurality of groups from the main pipe, and a main stopper having a test stopper is provided at a branch position from an upper group to a lower group. The method for leak inspection of underground buried equipment pipe according to claim 1. 3. The pressure measuring device has a built-in pressurizing device, which pressurizes an inspection point by the pressurizing device and compares the initial pressure with a pressure change after a lapse of a predetermined time. Or the leak inspection method of underground buried equipment piping described in 2. 4. The method for inspecting leaks in underground facility piping according to claim 3, wherein the pressurized fluid of the pressurizing device is a gas.